Return-Path: Received: from smtp1.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by lists.linuxfoundation.org (Postfix) with ESMTP id 63AB3C0001 for ; Mon, 22 Feb 2021 05:16:38 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id 4B3008355F for ; Mon, 22 Feb 2021 05:16:38 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id s6bS5C3ml7sw for ; Mon, 22 Feb 2021 05:16:37 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0 Received: from azure.erisian.com.au (cerulean.erisian.com.au [139.162.42.226]) by smtp1.osuosl.org (Postfix) with ESMTPS id F056383508 for ; Mon, 22 Feb 2021 05:16:36 +0000 (UTC) Received: from aj@azure.erisian.com.au (helo=sapphire.erisian.com.au) by azure.erisian.com.au with esmtpsa (Exim 4.92 #3 (Debian)) id 1lE3aA-0002cb-Im; Mon, 22 Feb 2021 15:16:32 +1000 Received: by sapphire.erisian.com.au (sSMTP sendmail emulation); Mon, 22 Feb 2021 15:16:24 +1000 Date: Mon, 22 Feb 2021 15:16:24 +1000 From: Anthony Towns To: Matt Corallo , Bitcoin Protocol Discussion Message-ID: <20210222051624.6eklzfec2bf4lqdk@erisian.com.au> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20170113 (1.7.2) X-Spam-Score-int: -18 X-Spam-Bar: - Cc: Michael Folkson Subject: Re: [bitcoin-dev] Yesterday's Taproot activation meeting on lockinontimeout (LOT) X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 22 Feb 2021 05:16:38 -0000 On Fri, Feb 19, 2021 at 12:48:00PM -0500, Matt Corallo via bitcoin-dev wrote: > It was pointed out to me that this discussion is largely moot as the > software complexity for Bitcoin Core to ship an option like this is likely > not practical/what people would wish to see. > Bitcoin Core does not have infrastructure to handle switching consensus > rules with the same datadir - after running with uasf=true for some time, > valid blocks will be marked as invalid, I don't think this is true? With the current proposed bip8 code, lockinontimeout=true will cause headers to be marked as invalid, and won't process the block further. If a node running lockinontimeout=true accepts the header, then it will apply the same consensus rules as a lockinontimeout=false node. I don't think an invalid header will be added to the block index at all, so a node restart should always cleanly allow it to be reconsidered. The test case in https://github.com/bitcoin/bitcoin/pull/19573/commits/bd8517135fc839c3332fea4d9c8373b94c8c9de8 tests that a node that had rejected a chain due to lockinontimeout=true will reorg to that chain after being restarted as a byproduct of the way it tests different cases (the nodes set a new startheight, but retain their lockinontimeout settings). (I think with the current bip8 code, if you switch from lockinontimeout=false to lockinontimeout=true and the tip of the current most work chain is after the timeoutheight and did not lockin, then you will continue following that chain until a taproot-invalid transaction is inclued, rather than immediately reorging to a shorter chain that complies with the lockinontimeout=true rules) Cheers, aj